A television station recently turned to NSL Analytical to help investigate the presence of lead in dental crowns.
Samples for the ICP/MS are prepared in platinum crucibles.
prepares final solution of samples for analysis in the ICP/MS instrument.
We’ve all heard the news stories about lead
found in toys imported from China.
WBNS, a Columbus, Ohio,
television station, recently investigated the presence of lead in dental
crowns, bridges and dentures produced in Asia.
The station’s 10 Investigates team began looking into this story after a
patient, based on the results of testing by NSL Analytical, sued her dentist
over the presence of lead in her dental
The station found that most dentists rely on
outside labs to make their crowns, and that these labs increasingly outsource
their work to India, Mexico and China. To check on the safety of
crowns imported from China,
10 Investigates obtained eight crowns from four labs in China that
advertise in industry magazines. Using a hand-held nondestructive device that
screens for lead, the reporters identified one crown as being positive for
The aqueous solution is introduced into the plasma
flame of the ICP/MS instrument to determine lead levels.
The station sent the crown to NSL for a more in-depth analysis.
NSL separated the porcelain from the metal and dissolved the crown in acid to
create a solution that chemists use to test for lead.
Tests were run using an inductively coupled
plasma/mass spectrometer (ICP/MS) instrument. ICP/MS is a highly sensitive type
of mass spectroscopy that can determine element concentrations below one part
per trillion. Combining mass spectroscopy and ICP analysis in a single
instrument enables the detection of low-level concentrations of lead from parts
per billion to 0.1%. After the test on the crown was complete, the instrument
gave a reading of 210 parts per million (ppm) of lead, which NSL reported to the
In response to the story, the Ohio Dental Board adopted a recommendation asking
dentists to require their labs to disclose where their dental devices are made.
On the national level, the U.S. Food and Drug Administration (FDA) is reviewing
the station’s report and developing a strategy to address these findings on all
imported dental devices.
For additional information, visit www.wbns10tv.com or www.nslanalytical.com.